This invention covers a process for the manufacture of solid electrolytic capacitors whereby a sintered anode body connected with an anode wire by means of clamping fixtures.
Solid electrolytic capacitors consist of a sintered element of a rectifying metal (valve-metal) as represented, for example, by tantalum, niobium, aluminum or zirconium onto which, by means of an electrochemical process, a dielectrically active oxide layer is formed. A semiconducting oxide as represented, for example, by mangenese or lead oxide is, used generally in the case of solid electrolytic capacitors for the cathode. A graphite layer covered by a conductive silver laquer layer is used, for example, in contacting the cathode. These solid electrolytic capacitors are equipped with suitable housings such as metallic cups or plastic encapsulations.
In the known process of manufacturing the sintered element, the anode is connected to the anode wire, which is generally made from the same material as the anode, by means of a clamping fixture. After the processes of preforming, pyrolysis, (in order to generate the semiconducting oxide layer by pyrolytic decomposition of, for example, manganese nitrate) and coating, the anodes are individually separated from the clamping fixture. As the next step a solderable anode input wire, for example, made from nickel, is attached by welding to the anode contact. For this purpose the sintered element has to be individually refixtured in magazines or similar holders in order to bring the elements manually or automatically into position for welding.